Each team will take a short quiz covering physics principles related to balloon performance, and then attempt to loft as much sand as possible to a minimum altitude within a specified time window using a tethered hot air balloon.  Click here for the description of how to build a simple balloon for practice.  

Event Location and Time:

Apparatus and Materials:

1.    Each team will bring to the Olympiad the following items:

• A pre-constructed 6’ hot air balloon built from the Edmund Scientific kit (part number CR3071866 available at www.scientificsonline.com).  The only additional materials that may be added to the kit are cement (e.g. glue stick for making seams), tape, and string.  The kit may be modified as desired, but no additional envelope material may be added, and no other materials may be substituted for those provided in the kit.
• Support equipment, tools, and materials (e.g. tape, string) to aid in the operation and repair of the balloon.
• Calculators, pencils, erasers, blank scratch paper for use during the quiz and for computation during the flight competition.

2.    The following equipment will be provided:

• A burner and chimney to provide the hot air for balloon inflation and flight.  The chimney has a 7” diameter.  The burner will be strictly under control of the contest officials at all times and will be operated by the contest organizers only, under the verbal guidance of the balloon team during inflation.  Team members are at no time permitted to operate the balloon burner.  Violation of this safety rule will result in immediate disqualification from the event.
• Safety glasses and gloves for use during balloon inflation.
• A long pole with a hook at one end to aid in handling the balloon during inflation.  It is recommended that a loop of string be included at the top of the balloon to make use of this tool.
• A tether line system used to anchor the balloon to the floor.  The tether line, made of 15 pound test Kevlar thread, will end in a fishing swivel clip, which will attach it to the balloon.  A small flag will be tied into the tether line near the anchored end and used to score the event.
• Each team will be provided with a standard payload hopper (small cup), which will be suspended below the balloon.  This will be used to carry the sand payload.
• A “Talking Timer” digital stopwatch, which verbally counts down the remaining time interval.  This will be used to time the flight windows.
• Sand
• A digital scale to weigh the sand carried.
• Small plastic containers to keep and weigh the sand lofted by each team.
• Score sheets on which the officials will record the scoring information for each team.

 Event Rules:

2)    The competition will be conducted by the judges as follows:

• Each team will first be given a written quiz worth 100 points.  The allowed time for answering the quiz will be 15 minutes.
• Each team will be assigned a starting time at random.  The starting times shall be set to allow time between competition flight windows for preparation and staging of the next team.
• Ready Area:  The team next in line to fly will be permitted to have their balloon, equipment, and personnel staged in a “ready area” designated by the organizers five minutes before the assigned starting time.  The organizers will provide the team with its payload hopper no later than the start of this ready period.
• Flight Window:  The officials will announce the start of the flight window.  Once the flight window is open the team may make as many attempts as desired to loft sand payload material aboard their balloon to the minimum altitude so that it may be added to their score.  The suggested flight window is 5 minutes.
• Scoring:  In order for sand to be added to the final score, the balloon must lift off and ascend until a small flag, attached to the tether line has been lifted off the ground.  Once this has occurred, the tether line may be used to retrieve the balloon.  The sand will then be emptied into a container provided by the officials and kept in the possession of an official monitor during the flight period.  In order for the sand to qualify toward the final score, the flag must have lifted off the ground during the flight window.  The recommended distance from the flag to the fishing swivel clip at the tether end is 30 feet.
• Repairs:  Balloons damaged during flight attempts may be repaired during the flight window, but no additional time will be allotted for repairs.

Judging Criteria:

1. Total Score:  Once the flight window has expired, the officials will weigh the sand that has been collected in the team’s container.  The total score shall be the sum of the quiz score plus the mass of the sand lofted, in grams, with all fractions of a gram dropped.  In addition, the officials shall record the number of flights used to achieve the final score.  The team with the highest score shall be declared the winner.

2. Ties:  In the event of a tie, the team with the highest quiz score shall be declared the winner.  If a tie still exists, the team that lofted their sand in the fewest number of flights shall be declared the winner. 

3. Awards:  Gold, Silver, and Bronze medals will be awarded to the teams with the highest three scores, respectively.